Method and apparatus for packaging flexible duct

ABSTRACT

An axially collapsible duct is packaged by inserting the duct into an open end of a tube, placing an open end of a bag over a tube so that the bag encloses the open end of the tube, compressing the duct, ejecting the duct from the tube into the bag while the duct is compressed, closing the open end of the bag about the duct while the duct is compressed, and fastening the open end while it is closed to retain the duct within the bag in a compressed state. A negative pressure can be created within the tube as the duct is being collapsed and ejected into the bag to hold the bag about the open end of the tube and to prevent the duct from expanding within the bag.

O tlmted States Patent [191 [111 3,827,210 Smalley et al. Aug. 6, 1974 [54] METHOD AND APPARATUS FOR 3,377,945 4/1968 Davis 100/90 PACKAGING FLEXIBLE DUCT 3,624,982 12/1971 Marietta 53/l 12 B X [75] Inventors: Rodney Roger Smalley, Maumee;

John vendel staudinger, Curtice, Przmary ExammerTrav1s S. McGehee both of Qhio; Harve Morton Attorney, Agent, or Firm-Robert M. Krone; John D. Smith, Aurora, C010,; Brian Lee L'Ster Meeker, Toledo, Ohio [73] Assignee: Johns-Manville Corporation, [57] ABSTRACT A h C l mpd 0e 0 0 An axially collapsible duct 15 packaged by msertmg Filed: Jan. 2, 1973 the duct into an open end of a tube, placing an open 21 A L N 320 396 end of a bag over a tube so that the bag encloses the l 1 pp 0 open end of the tube, compressing the duct, ejecting the duct from the tube into the bag while the duct is 1 12 compressed, closing the open end of the bag about the 513/124 C, 53/124 D, 53/258 duct while the duct is compressed, and fastening the [51] Int. Cl B65b 63/02 e end while it is closed to retain the duct within Field 0f Search 53/24, 1 14, 124 R, 124 A, the bag in a compressed state. A negative pressure can 53/l24 124 124 22 112 be created within the tube as the duct is being col- 100/90 lapsed and ejected into the bag to hold the bag about the open end of the tube and to prevent the duct from [56] Refe en s Cited expanding within the bag.

UNITED STATES PATENTS 1,2|s,3 l4 3/1917 Read 53/114 x 8 Clams 9 Drawmg F'gures 1 T T 51a METHOD AND APPARATUS FOR PACKAGING FLEXIBLE DUCT BACKGROUND OF THE INVENTION This invention relates to a method and apparatus of packaging axially collapsible duct and in particular to a method and apparatus which take advantage of this characteristic of the duct to reduce the volume occupied by such a duct when it is packaged.

An axially collapsible duct, such as an air duct, has a high volume to weight ratio which presents both shipping and handling problems for the product prior to the time it is ready for installation. For many modes of shipping the cost of shipping an item is not only based on weight but also volume. Consequently, while the weights of axially collapsible air ducts are not great, the volume occupied by these ducts in their uncollapsed state results in a considerable increase in the shipping cost. In addition, the lengths of these axially collapsible ducts makes them awkward to handle and store at the job site prior to the time of installation.

SUMMARY OF THE INVENTION Accordingly it is an object of the present invention to collapse axially collapsible duct to approximately one third its normal length during packaging so that the duct can be shipped and handled at this reduced length prior to the installation of the duct.

The present invention provides a method of packaging an axially collapsible duct which includes inserting an axially collapsible duct into an open end of a tube, placing an open end of a bag over the tube with the bag enclosing the open end of the tube, compressing the duct, and ejecting the duct from the tube into the bag while the duct is compressed. The opened end of the bag is closed about the duct while the duct is compressed and the open end is fastened to retain the duct within the bag in a compressed state. The duct is compressed and ejected from the tube by means of a ram. The ram can be provided with exhaust ports to prevent a build-up of air pressure within the tube and an additional vacuum exhaust port which is connected to a vacuum pump to create a negative pressure within the tube. By creating a negative pressure within the tube the bag is held about the open end of the tube, the duct is prevented from expanding within the bag during ejection of the duct into the bag, and the bag can be necked down between an end of the duct and the open end of the bag so that the necked down portion of the bag can be fastened to retain the duct within the bag in a compressed state.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1-5 are longitudinal cross sectional views of the tube and ram assembly of the present invention which illustrate the process of the present invention;

FIGS. 6-8 illustrate a second embodiment of the present invention which utilizes a ram that differs from the ram of the first embodiment; and

FIG. 9 is a side view of the overall apparatus of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 9 a packaging apparatus of the present invention comprises a tubular housing 22, a

ram assembly 24, a drive assembly 26 and a vacuum assembly 28.

The tubular housing 22 is open at both its forward and its rearward ends 30 and 32 respectively and is affixed to a frame 34. The forward end 30 of the tubular housing is open to permit the insertion of an axially collapsible duct 36 into the tube for the packaging operation. The open rear end 32 of the tubular housing receives the ram assembly 24 of the apparatus. The frame 34 is affixed to the tubular housing adjacent the rearward end 32 of the housing so that a package or bag 38 can be placed over the forward end of the tube to receive an axially collapsed duct. While the tubular housing 22 is shown with a generally circular cross section, the housing can also have a rectangular cross section or other cross sectional configurations to conform with. the cross sectional configuration of the duct being packaged.

The ram assembly 24 of the present invention comprises a ram 40, a hollow shaft 42 and a coupling assembly 44 which couples the ram 40 to the drive assembly 26. The ram 40 has a peripheral configuration complementary to the interior wall of the tubular housing. In addition, the periphery of the ram can be provided with an O ring 46 or other suitable sealing means to effect a seal between the periphery of the ram and the interior surface of the tubular housing. The ram 40 has a forward face 48 adapted to engage the duct 36 that is being compressed within the tubular housing and a rear face 50 to which the hollow shaft 42 is welded or otherwise affixed. In addition, the ram is provided with a vacuum exhaust port 52 which extends through the central portion of the ram from the forward face 48 to the rear face 50 of the ram. The exhaust port 52 communicates with the hollow interior of shaft 42 which is coupled to the vacuum assembly 28 through the coupling assembly 44.

The coupling assembly 44 comprises a pair of rectangular plates 54 and 56 which are joined by four rods that extend between and are welded or otherwise affixed to the opposing faces of the plates 54 and 56. The plate 54 is welded or otherwise affixed to the terminal portion of the shaft 42 and is provided with a conventional hose coupling 60 to connect the hollow shaft 42 to the vacuum assembly 28. Coupling plate 56 is welded or otherwise affixed to the forward end of a piston shaft- 62 of the drive assembly.

The drive assembly 26 is a double acting pneumatic or hydraulic piston and cylinder assembly. The inlet and exhaust ports 64 and 66 are suitably pressurized and exhausted through a conventional control'valve 68 to both extend and retract the ram 40 as will be explained hereinafter.

The vacuum assembly 28 comprises a conventional hose reel assembly 70 and a conventional vacuum pump assembly 72. The vacuum pump 72 is coupled to the hose coupling 60 of shaft 42 by hose 74. A pair of guide bars 76 guide the hose down through the coupling assembly 44 to the hose coupling 60 to prevent the hose from becoming tangled. With this construction, as the ram 40 is moved toward the forward end of tubular housing 22 the hose 74 is played out from the hose housing 70. As the ram 40 is retracted to the rearward end of the housing, the hose 74 is wound up within the hose housing.

The packaging apparatus is provided with a conventional control system represented by box 78. The control system 78 actuates the control valve 68 for the drive assembly 26 and the vacuum pump 70 to effect the operation of the packaging apparatus as will be explained hereinafter.

FIGS. 6-8 illustrate a second embodiment of the present invention which is identical in construction to the first embodiment with the exception of the ram 80. The ram 80 has a peripheral configuration complementary to the configuration of the tubular housing 22 and can be provided with an O ring or other suitable sealing means to assure an air tight fit between the periphery of the ram and the housing 22. The ram 80 is provided with a vacuum exhaust port 82 which is centrally located in the ram and extends from a forward face 84 to a rear face 86 of the ram. The vacuum exhaust port 82 communicates with the hollow shaft 42 which is welded or otherwise suitably affixed to the rear face 86 of the ram 80. In addition to the vacuum exhaust port 82 the ram 80 is provided with one or more exhaust ports 88 which extend between the forward face and the rear face of the ram 80. In the embodiment shown, four exhaust ports 88 are spaced about the ram 80 between the vacuum exhaust port 82 and the peripheral surface of the ram. The rear face 84 of the ram is provided with a check valve 90. The check valve 90 is a flexible rubber member which is annular in configuration. The inner edge of the check valve is secured about the shaft 42 with the check valve normally lying flat against the rear face of the ram to seal off exhaust ports 88. However, when the ram 80 is moving from its retracted position to its extended position, air is forced out through the exhaust ports 88 and past the check valve 90 to prevent pressure from building up within the tubular housing during the packaging operation and/or to assist the vacuum pump which is also removing air from the tubular housing 22.

The main function of the exhaust ports 88 and the check valve 90 is to assist the vacuum pump so that a smaller capacity vacuum pump can be used for the apparatus. With the embodiment of FIGS. 1-5 the vacuum pump alone must exhaust air from the tubular housing 22. With the embodiment of FIGS. 6-8 the exhaust ports 88 work simultaneously with the vacuum pump 72 during the initial portion of the ram stroke to remove air from that portion of the tubular housing that is between the ram and the bag covered forward end of the tubular housing. As the ram moves forward, the volume forward of the ram decreases until a point is reached where the capacity of the pump is sufficient to create a negative pressure within the tubular housing. At this point the check valve 90 is drawn closed and a negative pressure is created within the tube that increases as the ram approaches the forward end of its stroke.

In operation a duct 36 is inserted within the tubular housing 22 with the ram 40 in its retracted position. Then, as shown in FIG. 2, an open end of a bag 38 is slid over the forward end 30 of the tubular housing enclosing the duct 36 within the housing 22. The controls 78 are then actuated. With the embodiment shown in FIGS. 1-5 the vacuum pump 70 and the drive assembly 26 are simultaneously actuated to create a negative pressure within the housing 22 and to start the movement of the ram 40 from the rear end 32 to the forward end 30 of the tubular housing 22. The creation of a negative pressure within the tubular housing 22 draws the bag 38 tightly about an outer surface of the tubular housing and retains the bag on the housing. As shown in FIGS. 3 and 4 the negative pressure created within the tubular housing 22 is sufficient to create an inwardly directed force on the closed end of the bag 38 which permits thetubular duct to be collapsed to the degree desired (e.g., one third its original length) with the ram 40 and the bottom of the bag 38 acting as the opposing surfaces between which the duct is collapsed. In FIG. 3 the negative pressure within the housing 22 has not reached its peak and the ram partially ejects the partially collapsed duct from the tube. However, as the negative pressure increases the forces acting on the bottom of the bag increase until the forces are great enough to effect the collapse of the duct to the desired degree. Once the duct is collapsed to the desired length the ram completely ejects the duct from the end of the tubular housing and pulls the bag 38 farther off of the tubular housing 22. As shown in FIG. 4 the ram travels forward until the forward face of the ram extends somewhat beyond the forward edge of the tubular housing 22. At this point the forward progress of the ram is arrested and the operator grasps the bag 38. The retraction of the ram to the rear of the tubular housing is then started with the vacuum pump still operating. When the ram is retracted back into the housing (FIG. 5) there is no support for the bag intermediate the end of the duct and the outer end of the tubular housing. Consequently, the vacuum which is still being applied causes the bag to neck down. To assist in this operation the operator twists the bag and then applies a clip or other fastening means to the necked down portion of the bag to effect the closure of the open end of the bag. After the ram 40 reaches the position shown in FIG. 5 and is back within the tubular housing, the vacuum pump is shut off by the control system 78 so that the operator does not have to pull against a vacuum to remove the bag from the tubular housing. The ram 40 continues to the rear end of the tubular housing for the next packaging operation.

Each packaging cycle takes only 10 to 15 seconds. While in the preferred embodiment the negative pressure created within the housing 22 is sufficient to cause inwardly directed forces on the end of the bag that are sufficient to effect the collapse of the duct between the end of the bag and the ram 40, it is contemplated that lower negative pressures could be utilized and the operator could assist in the compression by holding the end of the bag.

The embodiment of FIGS. 6-8 operates in the same manner as the embodiment in FIGS. 1-5 with the one exception pointed out above. The air within the tubular housing 22 between the ram 40 and the bag covered forward end is initially exhausted simultaneously through the exhaust ports 88 and the vacuum exhaust port 82.

What is claimed is:

l. A method of packaging an axially collapsible duct comprising:

a. inserting an axially collapsible duct into an open end of a tube,

b. placing an open end of a bag over the tube with the bag enclosing the open end of the tube,

c. compressing the duct,

d. ejecting the duct from the tube into the bag,

e. exerting a force on the bag in a direction opposing the movement of the duct into the bag to maintain the open end of the bag on the tube and to restrict expansion of the duct within the bag to maintain the duct compressed,

f. closing the open end of the bag about the duct while the duct is compressed, and

g. fastening the open end closed -to retain the duct within the bag in a compressed state.

2. A method as defined in claim 1 wherein the force is exerted on the bag by:

a. creating a negative pressure within the tube as the duct is being collapsed and ejected into the bag.

3. A method as defined in claim 2 including:

a. simultaneously collapsing the duct and ejecting the duct into the bag.

4. A method as defined in claim 1 including:

a. simultaneously collapsing the duct and ejecting the duct into the bag.

5. A method as defined in claim 4 including:

a. preventing a pressure build up within the tube during initial stages of the collapsing and ejecting operation, and

b. creating a negative pressure within the tube during a remainder of the collapsing and ejecting operation to exert the force on the bag in the direction opposing the movement of the duct into the bag.

6. A method as defined in claim 1 including:

a. closing the open end of the bag about the duct by twisting a portion of the bag that encloses the duct relative to a portion of the bag remaining about the tube to neck down bag between the duct and the tube.

7. An apparatus for packaging an axially collapsible duct comprising:

a. a tube which is open at one end for receiving a duct within the tube and for receiving a bag over the tube,

b. a ram within the tube for collapsing the duct and ejecting the duct from the tube into the bag, the ram having a forward face for contracting the duct and a rear face, the ram having a first exhaust port means passing from the forward surface to the rear surface to prevent a buildup of air pressure within the tube as the ram moves from the retracted position to the open end of the tube, the first exhaust port means having a check valve means for permitting air to flow through the exhaust port means i from the forward surface to the rear surface and for preventing air from flowing through the exhaust port means from the rear surface to the forward surface, and the ram having a second exhaust port on the forward surface which communicates within a vacuum pump to exhaust air from the tube and creates a negative pressure within the tube, and

c. drive means for moving the ram between a retracted position within the tube and the open end of the tube.

8. An apparatus as defined in claim 7 wherein:

a. the drive means for moving the ram moves the ram to a position at the open end of the tube where a forward surface of the ram projects beyond the open end of the tube prior to retracting the ram to the retracted position, and

b. the vacuum pump for creating a negative pressure continues to operate as the retraction of the ram is started to neck down the bag about the end of the duct. 

1. A method of packaging an axially collapsible duct comprising: a. inserting an axially collapsible duct into an open end of a tube, b. placing an open end of a bag over the tube with the bag enclosing the open end of the tube, c. compressing the duct, d. ejecting the duct from the tube into the bag, e. exerting a force on the bag in a direction opposing the movement of the duct into the bag to maintain the open end of the bag on the tube and to restrict expansion of the duct within the bag to maintain the duct compressed, f. closing the open end of the bag about the duct while the duct is compressed, and g. fastening the open end closed to retain the duct within the bag in a compressed state.
 2. A method as defined in claim 1 wherein the force is exerted on the bag by: a. creating a negative pressure within the tube as the duct is being collapsed and ejected into the bag.
 3. A method as defined in claim 2 including: a. simultaneously collapsing the duct and ejecting the duct into the bag.
 4. A method as defined in claim 1 including: a. simultaneously collapsing the duct and ejecting the duct into the bag.
 5. A method as defined in claim 4 including: a. preventing a pressure build up within the tube during initial stages of the collapsing and ejecting operation, and b. creating a negative pressure within the tube during a remainder of the collapsing and ejecting operation to exert the force on the bag in the direction opposing the movement of the duct into the bag.
 6. A method as defined in claim 1 including: a. closing the open end of the bag about the duct by twisting a portion of the bag that encloses the duct relative to a portion of the bag remaining about the tube to neck down bag between the duct and the tube.
 7. An apParatus for packaging an axially collapsible duct comprising: a. a tube which is open at one end for receiving a duct within the tube and for receiving a bag over the tube, b. a ram within the tube for collapsing the duct and ejecting the duct from the tube into the bag, the ram having a forward face for contracting the duct and a rear face, the ram having a first exhaust port means passing from the forward surface to the rear surface to prevent a buildup of air pressure within the tube as the ram moves from the retracted position to the open end of the tube, the first exhaust port means having a check valve means for permitting air to flow through the exhaust port means from the forward surface to the rear surface and for preventing air from flowing through the exhaust port means from the rear surface to the forward surface, and the ram having a second exhaust port on the forward surface which communicates within a vacuum pump to exhaust air from the tube and creates a negative pressure within the tube, and c. drive means for moving the ram between a retracted position within the tube and the open end of the tube.
 8. An apparatus as defined in claim 7 wherein: a. the drive means for moving the ram moves the ram to a position at the open end of the tube where a forward surface of the ram projects beyond the open end of the tube prior to retracting the ram to the retracted position, and b. the vacuum pump for creating a negative pressure continues to operate as the retraction of the ram is started to neck down the bag about the end of the duct. 